There are 1–2 genera in the Diarrheneae. The tribe is sometimes placed in the Bambusoideae, sometimes in the Poöideae. Its inclusion in the Bambusoideae is supported by embryo characteristics and not strongly opposed by others, but it lacks some of the diagnostic features of that subfamily, e.g., fusoid cells, leaf blades with evident cross venation, and a complex midvein. Its inclusion in the Poöideae reflects the findings of the Grass Phylogeny Working Group (2001).